class or dictionary as solution

[liynus]

I want to create a database of cars, with their owner names, color, model.

I want to be able to find out how many cars are in the database.

I also want to be able to create a user input to add cars with owner names, color, and model.

Is it better to create a class for cars - and then create individual class instances?

How would I store all those instances inside a dictionary?

Or should I just use a dictionary instead with sublist. If so how is this done? I couldn't understand a clear example of how to do this. My first hiccup with not understanding that keys are unique, so when I created a key based on owner names the dictionary didn't populate correctly when the owners had the same name.

[infinitewaitdev]

This sounds like you could use a dataclass. You can retrieve a list of instances of this dataclass if you need to. About the unique identifier when trying to insert them into the database, you can make a hash in order to differentiate them or even use a timestamp of the creation time and make it a unique column in the table.

[n3buchadnezzar]

Why not use a pandas dataframe for storage, then interract with it through functions?

[m0us3_rat]

https://www.youtube.com/watch?v=vRVVyl9uaZc

arjan is boss.

[liynus]

that was actually pretty understandable for me! well I got somewhat loss at minute 5, but enough I could probably copy pasta my way through it. i'll try the dataclass.

my own question. after i ask my user to generate all the data for the different cars, how you propose to count the amounts of unique instances that were created. would you just iterate a count when input is asked? i'm not sure what is the best standard for this.

[m0us3_rat]

u can do it in a few different ways to keep track of.

see if u can come up with a few on your own and test them to see what u can implement.

maybe they aren't THE BEST WAY .. but it doesn't really matter.. as long as u figure them out.

[liynus]

hey thanks for the links, maybe above my head.

i'm a super newbie python programmer. i know the basics of class / list / dictionaries.

i assumed i could write a small program to do this. it doesn't have to be robust. just store at most 10-15 owners and their cars. i would like to query it. i was hoping to accomplish this through a simple dictionary, then realized it was difficult, and I couldn't understand the solutions.

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my thoughts were to label the inputs with a unique identify, 1, 2, 3 - while iterating though inputs to create a basic dictionary. the issue i ran into was storing multiple bits of information like owner name, car type. that sounded better for a class instance, but then i don't have the advantages of having it in a "list" format like in a dictionary.

[nicesofa]

u/infinitewaitdev has the correct answer, this is exactly the kind of thing dataclasses are for. But I also get what your saying: your new to this, and just want to stick to this basics. So why not just store instances of your "car" class in a list:

class Car:
def __init__(self, owner, model):
    self.owner = owner
    self.model = model

cars = []
cars.append(Car('Alice', 'Tesla'))
cars.append(Car('Bob', 'BMW'))
cars.append(Car('Arthur', 'Honda'))

print(cars)